Two sagging PG&E power lines ignited a deadly blaze last year in Northern California that killed four people, injured one firefighter and scorched nearly 10,000 acres — but no criminal charges will be filed against Pacific Gas & Electric Co., officials said Tuesday.

The Cascade Fire broke out in Yuba County on Oct. 8, 2017, after strong winds caused two power lines to touch, according to a report released by the California Department of Forestry and Fire Protection.

The power lines, owned by Pacific Gas and Electric Co., then created an electrical arc that unleashed molten material onto dry vegetation, Cal Fire said.

In total, the blaze burned 9,989 acres, destroyed 264 structures and killed four people, including a 77-year-old woman who was attempting to escape the inferno when she drove off the roadway, struck a tree and died, authorities said.

The investigation was sent to the Yuba County district attorney’s office, which announced Tuesday that it would not file criminal charges in the case.

“This office has concluded that a criminal jury would be unable to unanimously agree beyond a reasonable doubt that the evidence is sufficient to establish criminal negligence,” a statement from District Attorney Patrick McGrath read.

PG&E released a statement saying that despite its efforts to inspect overhead electrical lines and prune trees in the area, the drought and dry weather have increased the chances for wildfires.

“In light of this, we recognize we all need to do even more to help reduce the risk of wildfires, and are committed to working together with our state and community partners to develop comprehensive safety solutions for the future,” PG&E said.

The utility has taken measures to reduce fire risk by launching an operations center to monitor fire threats and shut off power to certain areas during extreme fire conditions.

At least a dozen wildfires that scorched Northern California last October, including the deadly Atlas and Nuns fires in the North Bay, were caused by PG&E power lines, Cal Fire said in June.

Investigations determined that downed power lines or trees and branches coming into contact with power equipment sparked eight fires in Sonoma and Napa counties, resulting in eight fatalities.

The utility’s equipment was also responsible for Mendocino County’s Redwood Fire, which left nine dead, and three smaller blazes in Lake, Humboldt and Butte counties, according to Cal Fire.

PG&E violated state law in eight of the 12 fires, Cal Fire said, but officials did not specify which laws were broken.

The cause of the Tubbs Fire, which destroyed thousands of homes and killed 22 people in Sonoma County, is still under investigation.

The new law will allow the utility to use a state-authorized bond to pay for more than 200 lawsuits filed against them in the past year.

In order for that state-authorized bond to be put to use, the California Public Utilities Commission has to determine that the utility acted reasonably in maintaining its equipment before the 2017 blazes.

If that occurs, the bonds will be paid off over time by PG&E’s customers. If the commission determines that PG&E did not act reasonably, then the utility and its shareholders will cover the cost.